Automatic blind riveting machines

ABSTRACT

A machine for successively installing pull-to-set type blind rivets has a head reciprocable toward and from a setting position, a rivet delivering mechanism including a gate for holding a rivet with its stem foremost, and means for pivoting the head when retracted to enable it to receive the stems of the successive rivets positioned at said gate.

United States Patent Enock 14 1 Apr. 25, 1972 [54] AUTOMATIC BLIND RIVETING [56] References Cited MACHINES UNITED STATES PATENTS [721 Invent: Clive Birmingham England 3,179,319 4/1965 Barker et al. ..227/117 x [73] Assignee: USM Corporation, Boston, Mass. 3,190,523 6/1965 Van Ril'sewilk 17 X I 3,237,832 3/1966 Wilson ..227/117 Flledi 1970 3,580,457 5/1971 Henshaw 1 ..227/1l6 A l. [21] pp NO Primary Emminer-Granville Y. Custer. Jr.

Attorney-Richard A. Wise. Richard B. Megley and Carl E. [30] Foreign Application Priority Data Johnson Mar. 20, 1970 Great Britain ..l3,692/70 [57] ABSTRACT [52] U.S.Cl ..227/5l,227/112,227/117 A machine for successively installing pull-to-set type blind [51] Int. Cl. ..B21j 15/10 rivets has a head reciprocable toward and from a setting posi- [58] Field of Search ,.227/51, 52, 53, 55, [14, 115 tion, a rivet delivering mechanism including a gate for holding a rivet with its stern foremost, and means for pivoting the head when retracted to enable it to receive the stems of the successive rivets positioned at said gate.

7 Claims, 5 Drawing Figures PATENTED APR 2 5 1972 SHEET 10F 2 [nvemor Clive R Ffzock By his Afforney AUTOMATIC BLIND RIVETING MACHINES CROSS REFERENCE TO RELATED APPLICATION An application Ser. No. 824,946, filed May 15, 1969 in the name of James N. Henshaw, now US. Pat. No. 3,580,457 issued May 25, 1971 discloses a blind riveting machine wherein lowermost fasteners of a raceway are successively delivered to a riveting head by a transfer mechanism which orients the fastener.

BACKGROUND OF THE INVENTION This invention is concerned with providing mechanism for enabling a blind riveting machine cyclically to receive and install pull-to-set type fasteners. These comprise a hollow rivet and a mandrel having a stem axially disposed therein. The

mandrel is provided with a head larger than the bore of the rivet and initially disposed beyond its blind end. Accordingly, a tool or machine in setting such rivet assemblies pulls the mandrel stem relatively to the rivet to cause its blind end to bev radially expanded.

In the machine disclosed'in the Henshaw application above cited, a blind riveting head is mounted for reciprocation toward and from a rivet setting zone, and a transfer deviceis laterally movable to orient and present each rivet in aligned position so that its mandrel may be received by the head as it advances toward the rivet setting position.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved blind riveting machine, and more especially to provide an improved means whereby its head may be automatically supplied with successive mandrel-rivet assemblies to be installed.

As shown herein, and in accordance with a feature of the present invention, a blind riveting machine has its head mounted on a carriage for reciprocation toward and from a rivet setting position, and the head when retracted is also mounted for rotation about an axis and toward and away from a rivet receiving position. Also mounted on the carriage is a gate mechanism associated with a delivery tube of mechanism for feeding the mandrel-rivets. When the head is rotated to its rivet receiving position its nosepiece is registered with the gate mechanism to receive the stem of a mandrel therefrom. Suction applied through the nosepiece bore draws in a portion of the mandrel stem, and return pivotal movement of the head from rivet receiving position causes the gate mechanism to release the fastener which is thereupon under control of the head. The supply tube is preferably flexible and adapted to permit the mandrel-rivets to be blown through it for delivery successively to the same machine or additional riveting machines.

While the illustrative machine is fitted with a stationary gate means and a head that is relatively movable into rivet receiving position, it will be understood that according to the invention another machine may have one or more heads relatively to which a single delivery gate mechanism is moved.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other features of the invention will now be more particularly described in connection with an illustrative embodiment and with reference to the accompanying drawings thereof in which:

FIG. 1 is a view in right-hand side elevation of the illustrative machine with a blind riveting head of the machine in vertical retracted position;

FIG. 2 is a view in front elevation of gate means of the machine shown in FIG. 1, and partly in section;

FIG. 3 is a view in right-hand side elevation of the gate means of the illustrative machine and shown partly in section;

FIG. 4 is a view'similar to FIG. 2 but showing the nosepiece of the machine shifted into register with the gate means; and

FIG. 5 is a view similar to FIG. 3 and showing a rivet in delivery or head loading position.

Referring to FIG. 1, a blind riveting machine has a head generally designated 10. It may be of the type disclosed in the Henshaw application or any other suitable construction for pulling the mandrel M (FIG. 5) to set a rivet R of a blind rivet assembly in a work piece. The head 10 includes a nosepiece 11 (FIGS. 1 and 5) having a mandrel receiving bore and internal gripping means such as collet jaws not herein shown. The head 10 is pivotally supported on a lower end of an arm 12 by a pin 9 for rotation, when retracted from the work piece, between a vertical position (FIG. 1,) and a horizontal rivet receiving position (FIG. 5). The arm 12 is secured to and extends downwardly from a carriage 13 which is mounted for vertical reciprocation, the carriage being thus guided by spaced slide bars. The carriage 13 is raised and lowered along the guideway preferably by a double acting pneumatic drive cylinder provided with a piston rod projecting vertically and having its lower end secured to the carriage.

Mounted on the carriage 13 is a double acting pneumatic motor 14 which is arranged to drive two horizontal, coaxial pins 16 projecting therefrom along vertical paths. The motor 14 acts through the pins 16 to control pivotal movement of the head 10 to and from a rivet-receiving position as later described. Mounted on each pin 16 is an upper end of a triangular link 18. Each link is secured on its pin 16 by a nut 20. Mounted on a lower comer of each link 18 is a cylindrical roller 19 free to rotate and move laterally between parallel walls of guideway portions 24 of a guide member secured to the head 10. The two links 18 are rigidly interconnected at apex corners by a horizontal tie bar 26 having threaded end portions which are received through holes in the links 18 and the links are secured thereon by nuts 28. Pivotally secured to each link member 18 at 29, mid-way between the upper and lower corners of the link member, is an upper end of an arm 30 which has a lower end pivotally secured, at 31, to a mounting block portion 32 of the carriage.

Blind-rivet supply means next to be explained comprises a vibratory hopper or the like (not shown) with escapement means which is adapted to release fasteners one at a time, mandrel stem foremost, into one end of a flexible tube 34. A delivery end of the tube 34 extends into a bore formed in gate means generally designated 36 (FIGS. 1-5) which is secured to the mounting block portion 32 of the carriage. Compressed air is desirably applied to blow the mandrel rivet along the tube to the gate means 36 from the hopper. The gate means 36 comprises a back plate 38 with flange portions 40 to enable it to be attached by bolts to an underside of the mounting block portion 32 of the carriage 13. On a front face of the back plate 38 are mounted an upper block 42 and two cooperative jaws 44 and 45. A flat, front plate 46 is secured by screws 48 to a front face of the block 42 so as to cover upper portions of the jaws. Two pivot pins 50 and 51 pass through the front plate 46, through the jaws 44 and 45, respectively, and into the back plate 38. The jaws 44 and 45 are thus pivotally held between the front plate 46 and the back plate 38. The flexible tube 34 is received in a horizontal cylindrical bore through the back plate 38, a smaller diameter portion of substantially the same diameter as the inside diameter of the tube 34 extending coaxially through the front face of the plate 38. When in a closed position the jaws 44 and 45 each provide half of a cylindrical bore which is coaxial with the bore in the back plate 38 and which comprises a rear, major diameter portion 52, an intermediate, forwardly converging, conical portion 54 and a front, minor diameter portion 56. Pivotally mounted on a horizontal pin 58 secured into a front face of one of the jaw members 44 is astop latch 60 which is urged by a leaf spring 62, secured by screws 63 to a lower edge surface of the front plate 46, into a position in which it closes a front end of the minor diameter portion 56 of the bore provided by the jaws. The two jaws 44 and 45 are urged into their closed position by a leaf spring 64 which passes around them so as to be resiliently displaced when they are opened. A horizontal centralizing peg 66 secured into the front face of the back plate 38 and extending in a direction parallel to the bore provided by the jaws 44 and 45 engages upper surfaces of the jaws when they are in the closed position to prevent travel of either jaw beyond its closed position.

In the operation of the machine the escapement of the rivet supply means is signaled to release a mandrel-rivet assembly into the flexible tube 34, and compressed air is admitted to blow the assembly therealong, stem-first, to the gate means 36. With the head in its upwardly retracted position, compressed air is then admitted to the pneumatic motor 14 which drives the two pins 16, and hence also the upper corners of the links 18, vertically downwards. As the pins 16 descend motion is transmitted by way of the links 18 and the arms 30, to the rollers 19 the axes of which are moved towards the head 10. The parallel walls of the guideway portions 24 in which the rollers 19 are slidably located are so inclined to the direction of movement of the axes of the rollers that they are engaged by the rollers and a turning moment, counterclockwise as viewed in FIG. 1, is applied to the head 10. As the pins 16 are driven downwards by the motor 14 the roll 19 remain in engagement with the walls of the guideway portions 24 to turn the head about its horizontal axis of rotation from its vertical position until, when the pins 16 reach the limit of their downward movement, it assumes its horizontal, rivet-receiving position shown in FIG. 5. The head 10 and gate means 36 are so arranged on the carriage that as the head arrives at its rivetreceiving position its nosepiece ll lifts the latch 60 upwardly as shown in FIG. 4 and its longitudinal bore becomes coaxial and in communication with the bore provided by the rivet constraining jaws 44 and 45 of the gate means 36. Suction is applied by the head 10 through its axial bore so that the mandrel of the rivet assembly at the gate means is partly drawn through the minor diameter portion 56 of the bore provided by the jaws 44 and 45 into the hole in the nosepiece 11 until a head flange of the rivet of the fastener assembly engages the wall of the conical portion 54 ofthe bore.

Compressed air is now applied to the motor 14 to drive the pins 16 vertically upwards to rotate the head 10 back to its vertical position. As the head 10 is reversely rotated and leaves its rivet-receiving position, with suction still applied to the mandrel rivet by the head 10, the jaws 44 and 45 are displaced apart, as the mandrel M is swung downwardly by the nosepiece 11, against the action of the spring 64, by the cam action thereon of the head flange of the rivet and thus allow the mandrel-rivet to be withdrawn downwardly from them. Also as the head leaves, the spring 62 urges the latch 60 back into its bore closing position.

When the head 10 of the illustrative machine is returned to its vertical retracted position by the motor 14, with mandrel rivet M-R held in the nosepiece 11 by suction, it is advanced rectilinearly to a work piece (not shown) in which the rivet is to be set. When the work piece is presented below the head 10, for example by conveyor means of an automatic assembly line, compressed air is admitted to the drive cylinder to move the carriage 13 down the guideway to advance the loaded head 10 to its advanced rivet-setting position. The rivet is set in the work piece by mandrel-pulling operation of the head 10 and the head is then retracted from the work piece by the drive cylinder. The illustrative machine is then ready for another cycle of operation commencing with release of the next mandrel-rivet by the escapement means into the tube 34.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a machine for installing pull-to-set mandrel-rivets having a reciprocable head provided with a nosepiece bore for receiving a mandrel, a carriage for slidably mounting the head, and means for reciprocating the head axially toward and from a rivet setting position, mechanism for delivering successive mandrel-rivets stem foremost to a predetermined position adjacent to the retracted position of the head, and mechanism mounted on the carriage for causing the nosepiece bore of the head when retracted to be brought into register with said predetermined position for the reception of a mandrel stem.

2. A machine as in claim 1 wherein the delivery mechanism includes a flexible tube, and a gate means at the delivery end of the tube for positioning the mandrel-rivets axially thereof.

3. A machine as in claim 2 wherein the gate means includes a pair of cooperative jaws yieldingly separable from a position wherein they are engageable with a mandrel-rivet delivered by the tube, said jaws being displaceable to release the mandrelrivet to said head by operation of said nosepiece registering mechanism.

4. A machine as set forth in claim 1 wherein the carriage is adapted to guide the head vertically along its longitudinal axis, said mandrel-rivet delivering mechanism is disposed to present each mandrel-rivet horizontally, and said nosepiece registering mechanism comprises linkage interconnecting the head and the carriage for pivoting the head substantially about a horizontal axis, the registering mechanism further including fluid pressure actuated means for operating the linkage between reciprocatory movements of the head in a cycle of operations.

5. In a machine having a reciprocable head provided with a nosepiece for receiving and setting blind mandrel-rivets, a carriage for slidably mounting the head, power means on the carriage for cyclically moving the head toward and from a work piece in which a mandrel-rivet is to be set, delivery means including a tube for positioning successive mandrel-rivets stem foremost, and mechanism automatically operable when said power means has retracted the head from the work piece to rotate the head for register of its nosepiece into mandrelreceiving relation with the delivery end of the tube.

6. A machine as set forth in claim 5 wherein both the head reciprocating mechanism and the head rotating mechanism are fluid pressure operated, and suction is applied to a bore in said nosepiece to enable it to retain therein a stem of the mandrel received from the tube.

7. A machine as set forth in claim 5 wherein there is interposed between the delivery end of the tube and the nosepiece when registered therewith a gate means operable by the nosepiece, said gate means being adapted to release a mandrel-rivet to the nosepiece upon relative separating movement of the latter. 

1. In a machine for installing pull-to-set mandrel-rivets having a reciprocable head provided with a nosepiece bore for receiving a mandrel, a carriage for slidably mounting the head, and means for reciprocating the head axially toward and from a rivet setting position, mechanism for delivering successive mandrelrivets stem foremost to a predetermined position adjacent to the retracted position of the head, and mechanism mounted on the carriage for causing the nosepiece bore of the head when retracted to be brought into register with said predetermined position for the reception of a mandrel stem.
 2. A machine as in claim 1 wherein the delivery mechanism includes a flexible tube, and a gate means at the delivery end of the tube for positioning the mandrel-rivets axially thereof.
 3. A machine as in claim 2 wherein the gate means includes a pair of cooperative jaws yieldingly separable from a position wherein they are engageable with a mandrel-rivet delivered by the tube, said jaws being displaceable to release the mandrel-rivet to said head by operation of said nosepiece registering mechanism.
 4. A machine as set forth in claim 1 wherein the carriage is adapted to guide the head vertically along its longitudinal axis, said mandrel-rivet delivering mechanism is disposed to present each mandrel-rivet horizontally, and said nosepiece registering mechanism comprises linkage interconnecting the head and the carriage for pivoting the head substantially 90* about a horizontal axis, the registering mechanism further including fluid pressure actuated means for operating the linkage between reciprocatory movements of the head in a cycle of operations.
 5. In a machine having a reciprocable head provided with a nosepiece for receiving and setting blind mandrel-rivets, a carriage for slidably mounting the head, power means on the carriage for cyclically moving the head toward and from a work piece in which a mandrel-rivet is to be set, delivery means including a tube for positioning successive mandrel-rivets stem foremost, and mechanism automatically operable when said power means has retracted the head from the work piece to rotate the head for register of its nosepiece into mandrel-receiving relation with the delivery end of the tube.
 6. A machine as set forth in claim 5 wherein both the head reciprocating mechanism and the head rotating mechanism are fluid pressure operated, and suction is applied to a bore in said nosepiece to enable it to retain therein a stem of the mandrel received from the tube.
 7. A machine as set forth in claim 5 wherein there is interposed between the delivery end of the tube and the nosepiece when registered therewith a gate means operable by the nosepiece, said gate means being adapted to release a mandrel-rivet to the nosepiece upon relative separating movement of the latter. 